Recycling in the Biosphere Unlike the one-way flow of energy, matter (substances that a physical object is composed of: the matter of which the earth is made) is recycled within and between ecosystems. Elements (C = carbon; H = hydrogen, N = nitrogen, O = oxygen, P = phosphorus) pass from one organism to another and among parts of the biosphere through closed loops called biogeochemical cycles, which are powered by the flow of energy.

Recycling in the Biosphere Biogeochemical cycles of matter involve biological processes, geological processes, and chemical processes. As matter moves through these cycles, it is never created or destroyed—just changed. Biogeochemical cycles of matter pass the same atoms and molecules around again and again.

Chemical and Physical Processes Biological Processes Biological processes consist of any and all activities performed by living organisms. * eating * breathing * eliminating waste * “burning” food (cellular respiration) Geological Processes Geological processes include volcanic eruptions, the formation and breakdown of rock, and major movements of matter within and below the surface of the earth. Chemical and Physical Processes Chemical and physical processes include the formation of clouds and precipitation, the flow of running water, and the action of lightning.

The Water Cycle Water molecules typically enter the atmosphere as water vapor when they evaporate from the ocean or other bodies of water. Water can also enter the atmosphere by evaporating from the leaves of plants in the process of transpiration.

Nutrient Cycles * The chemical substances that an organism needs to sustain life are called nutrients. * Every organism needs nutrients to build tissues and carry out life functions. * Nutrients pass through organisms and the environment through biogeochemical cycles.

OXYGEN Oxygen participates in parts of the carbon, nitrogen, and phosphorus cycles by combining with these elements and cycling with them through parts of their journeys. Oxygen gas in the atmosphere is released by one of the most important of all biological activities: photosynthesis. Oxygen is used in cellular respiration by all multicellular forms of life, and many single-celled organisms as well.

Carbon Cycle Carbon is a major component of all organic compounds, including carbohydrates, lipids, proteins, and nucleic acids. Carbon dioxide is continually exchanged through chemical and physical processes between the atmosphere and oceans. Plants Animals Industry & Vehicles Organic Material Fossil Fuels Photosynthesis Respiration Decomposition Burning Pumping

The Carbon Cycle

The Carbon Cycle Biological processes 1. Plants take in carbon dioxide during photosynthesis and use the carbon to build carbohydrates (sugar, starch) 2. Carbohydrates then pass through food webs to consumers. 3. Organisms release carbon in the form of carbon dioxide gas by respiration. 4. When organisms die, decomposers break down the bodies, releasing carbon to the environment.

The Carbon Cycle Geological processes 5. Geologic forces can turn accumulated carbon into carbon-containing rocks or fossil fuels. Human Activity 6. Carbon dioxide is released into the atmosphere by volcanic activity or by human activities, such as the burning of fossil fuels and the clearing and burning of forests.

Carbon Cycle photosynthesis respiration SHORT TERM LONG TERM organisms produce wastes or decompose forms fossil fuels shells & bones becomes limestone rock http://www.youtube.com/watch?v=U3SZKJVKRxQ

Carbon Cycle HUMAN ACTIVITY (IMPACT): Burning fossil fuels (vehicles, factories, heating systems, electricity, etc.) releases carbon dioxide (CO2) into the atmosphere Too much CO2 in the atmosphere may lead to global warming!

The carbon cycle with and without humans In 1750, WITHOUT industry & vehicles, there was around 280 CO2 molecules in every million air molecules In 2007, WITH industry & vehicles, there is now 380 CO2 molecules in every million air molecules (35% increase) Plants Animals Industry & Vehicles Organic Material Fossil Fuels Atmosphere Photosynthesis Respiration Decomposition Burning Pumping Plants Animals Organic Material Atmosphere Respiration Decomposition Photosynthesis Fossil Fuels 13